x/x-1 + x+1/ x+3 = 1/x^2+2x-3
x(x+3)+(x+1)(x-1)/(x-1)(x+3) = 1/x^2+2x-3
x^2+3x+x^2-x+x-1/(x-1)(x+3) = 1/x^2+2x-3
x^2+3x+x^2-x+x-1/(x-1)(x+3) = 1/x^2+2x-3
2x^2+3x-1/(x-1)(x+3) = 1/x^2+2x-3
2x^2+3x-1/ x^2+2x-3- 1/x^2+2x-3=0
2x^2+3x-1-1/x^2+2x-3=0
2x^2+3x-2/x^2+2x-3=0
2x^2+3x-2=0
d=9+16=25=5^2
x1=-3+5/4=2/4=1/2
x2=-3-5/4=-8/4=-2